VDO MS 5000 -, User Manual

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General Information
124
GPS (Global Positioning System)
The GPS system is based on the reception of navigation sig-
nals from a total of 27 GPS satellites which orbit the earth
at an altitude of 21,000 km in approximately 12 hours.
The signals from at least 4 satellites have to be received for
three-dimensional positioning, i.e. according to length,
width and altitude.
The accuracy attainable is thus approximately 30 m to
100 m. If the signals of only three satellites can be received
then only two-dimensional positioning without determina-
tion of the altitude is possible. The accuracy of the calcu-
lated position is thus reduced.
Altogether, the integrated system receiver can receive the signals of up to 8 satellites
at the same time.
If the vehicle is parked for longer periods of
time, then the satellites continue their orbit.
Thus it may take several minutes before the sig-
nals of enough satellites have been received and
analysed after the ignition has been switched on
again.
Sufficient reception (three-dimensional position) is shown by means of the green
satellite symbol in the display. The received satellites (total number) are shown as yel-
low stars in the GPS display. The symbol remains red if GPS reception is insufficient.
Thus the functioning of the system may be temporarily restricted after a vehicle has
been stationary for a longer period of time. The system will operate reliably once GPS
reception is again sufficient.
DE-IT-E_MO_MS5000.book Page 124 Sunday, November 7, 1999 10:57 PM